Datasheet

321
2545T–AVR–05/11
ATmega48/88/168
Figure 30-12. Idle supply current vs. V
CC
(32kHz external oscillator).
30.3 Supply current of I/O modules
The tables and formulas below can be used to calculate the additional current consumption for
the different I/O modules in Active and Idle mode. The enabling or disabling of the I/O modules
are controlled by the Power Reduction Register. See “Power reduction register” on page 41 for
details.
25°C
0
5
10
15
20
25
30
1.5 2 2.5 3 3.5 4 4.5 5 5.5
V
CC
(V)
I
CC
(µA)
Table 30-1. Additional current consumption for the different I/O modules (absolute values).
PRR bit Typical numbers
V
CC
= 2V, F = 1MHz V
CC
= 3V, F = 4MHz V
CC
= 5V, F = 8MHz
PRUSART0 8.0µA 51µA 220µA
PRTWI 12µA 75µA 315µA
PRTIM2 11µA 72µA 300µA
PRTIM1 5.0µA 32µA 130µA
PRTIM0 4.0µA 24µA 100µA
PRSPI 15µA 95µA 400µA
PRADC 12µA 75µA 315µA
Table 30-2. Additional current consumption (percentage) in active and idle mode.
PRR bit
Additional current consumption
compared to active with external clock
(see Figure 30-1 on page 315 and
Figure 30-2 on page 316)
Additional current consumption
compared to Idle with external clock
(see Figure 30-7 on page 318 and
Figure 30-8 on page 319)
PRUSART0 3.3% 18%
PRTWI 4.8% 26%
PRTIM2 4.7% 25%